Re: Green options - what gives the biggest return on investment?
The green technology just isn't there.
Geothermal takes approximately 3 years to balance, maintenance is expensive and cost recovery just doesn't seem to be there.
Wind generators require an almost constant 11 MPH wind to be viable, very few locations in this country for that.
photovoltaic with proper storage is viable but and to do an average home would cost about $25,000.
One place you can save is on one of the biggest energy hogs in the home and that is the water heater. Although tank-less water heaters are great if properly sized to provide unlimited hot water I don't see them saving much in energy under normal usage and have a high upfront cost that is not likely to be recovered. You can though go to a high efficiency WH like the Marathon if you have an electric WH.
It seems to me that the simplest solutions are what saves the most energy and money and have the quickest pay back like those mentioned by Jkirk or adding a storage tank with a simple solar heated exchanger in it to preheat water before it goes into the WH. Using lower wattage lights, putting electronic equipment such as computers or TVs on power strips so you can turn the power completely off when they are not in use. Cloths line is another energy saver that pays for itself very quickly. And don't be afraid of the dark, turn off all those all night security lights.
Be sure you live your life, because you are a long time dead.-Scottish Proverb